- Jacob Klein (1734) first used the term Echinodermata for sea urchins.
- Linnaeus in 1758 placed Asterias, Echinus and Holothuria under Mollusca.
- Lamarck (1801) included these animals in the order Echinoderm of the Class Radiata.
- In 1847 Leuckart gave phylum rank to the Echinodermata.
- The Echinoderms are spiny skinned animals.
- They are exclusively marine animals. They do not show distinct head.
- They show pentaradial symmetry.
- They show peculiar water vascular system of coelomic origin.
- They are coelomate animals with pentaramous radial symmetry, that is the body can be divided into five parts arranged around a central axis, but the larva is bilaterally symmetrical.
- They have an endoskeleton of calcareous ossicles made from mesoderm, there are also external spines which may be movable or fixed.
- Respiratory organs are minute gills protruding out from the coelome.
- There is no definite blood vascular system, it is represented only by lacunar tissue, there are no definite excretory organs.
- Nervous system forms a ring around the mouth with nerves radiating from it, it is the principal nervous system and is in contact with the ectoderm in addition there is a deeper nervous system lying In the mesoderm.
- Sexes are usually separate but copulation does not take place. Echinodermata have no parasitic forms.
INTRODUCTION TO PHYLUM ECHINODERMATA
By BS Media | Medically reviewed by a board-certified member
Published: June 05, 2017 | Updated: November 30, -0001
Previous topic INTRODUCTION TO PHYLUM MOLLUSCA
Read 1279 times
Get real-time alerts and all the latest updates on your phone with the BIOSCIENCE mobile app. Download from
BS Media is the group of authors and reporters of BIOSCIENCE PAKISTAN which get you to the breaking news about health and biology recent trends and updtaes.
Latest from BS Media
- in HemotologyScreening Tests for Infections Transmissible by Transfusion
- in HemotologyAdverse Effects of Transfusion
- in Dentistry10 Tips to Look After Your Teeth
- Stool Examination for Ova and Parasites
- By BS MediaIs the protection of mental health a priority taught in your schools?
- Bilirubin: Total, Direct and Indirect Bilirubin (Different Types of Jaundice)
- Serum Albumin Test: Purpose, Procedure, and Normal Values
- Adrenal Gland Hormones and Interpretation